Apparatus for injecting foam stabilizing solutions



Jan 23, 1940- L. G; M. TlMPsoN 2,188,066

APPARATUS FOR INJECTI-NG FOAM STABILIZING SOLUTIONS Filed oct. 2, 1957 2 Sheets-Sheet l Jan. 23, 1940.

APPARATUS FOR INJECTING FOAM STABILIZING SOLUTIONS I L. G. M. TIMPSON Filed Oct. 2, 1937 2 Sheets-Sheet 2 INVENTOR Patented Jan. 23, 1940 I v I UNITED STATES PATENT oFvFlcE APPARATUS Foa lNJEcTmG FOAM s'ramzme soLUTIoNs Lewin G. Moms rlmpsen, Plainfield, N. J., assignor to Pyrene-Minimax Corporation, Newark, N. J., a corporation oi' Delaware Application October 2, 19-37, Serial No. 166,637

3 Claims. (Cl. 169-14) This-invention relates to apparatus for intro- The invention willbe explained in conjunction ducing a solution of foam stabilizing material with the embodiment of the apparatus illustrated into a stream of another liquid such as water. in the a'cc'ompanying drawings, although it is to More particularly, the invention relates to the 'be understood that the invention is in no way introduction of a foam stabilizing solution into a limited to this embodiment. 5 stream of water in accordance with the rate In the drawings, Figure 1 is avertical secof flow of the water and without materially detional view of a container for holding foam stacreasing the head of the stream to provide a bilizing solution and illustrates an injecting apstream of liquid for producing iire extinguishing paratus at the top of said container. p

I foam. Figure 2 is an enlarged scale vertical sectional 10 In the art of producing iire extinguishing view of the injecting apparatus on the line 2--2 I foam, various methods have been used for the of Fig. 1 and showing a fragmentary upper porintroduction of foam stabilizing materials, either tion of the solution container. in solid form or in solution, into the bulk of the With reference to the drawings, numeral I ll liquid utilized for the production of foam. In indicates a cylindrical container which may be these methods of producing foam', water is the closed and sealed and which is supported in an principal ingredient and where water is available `upright position on suitable legs Il. The conunder asufcient head, it isV particularly desirable tainer may be conveniently constructed with a to utilize this head, not only-for the production top member i2' and a bottom member I3 welded a@ of the foam but also for the projection of the to the cylindrical side wall I4. Suitable means team on the re. Also, the rate of introduction are provided, preferably at the top and bottom of or foam. stabilizing material into a stream of thecontainer', for iling and emptying the same. water should be made dependent upon the rate The emptying arrangement at the bottom of the of iiow of the water, in order that the foam procontainer may comprise the valve I5 `normally duced may be of the desired uniform quality. held in tight engagement with the rim of the Heretofore, the introduction of foam stabilizopening I5 and carrying a suitable gasket I'I. ing material intoa water stream has required Valve I5 may be conveniently operated from the either an independent source of power, such as top of the container by means of' the rod I8 used with an injector pump, and usually the carrying a handle I9 and threaded at its bottom constant services of operators, or a very subinto a central opening 20 in the valve I5. Rod 30 stantial loss'in head of the water available. Es- I8 may be journaled in the bearing 2l at the top pecially where water is taken from a hydrant, it is I 2 of the container and preferably passes through desirable to preserve this head, so far as possible, a packing gland 22. for the projection of the foam upon the fire, and The upper portion of the container may be independent sources of power for injection ireprovided with a cap 23 having its lower portion 35 quently are not available near a re. A threaded into the filling opening 24 in the top v An'object of my invention is to provide an member I2 of the container and suitably provided apparatus for introducing foam stabilizing mawith a gasket 25, oi' rubber or other suitable terial in solution into a stream of water without material. The cap- 23 may be screwed and unrequiring the aid of lan independent source of screwed by means of the handle 26 and, if de- 40 power and without substantial loss of head in the sired, a petcock 21 may be provided therein to water stream.- l serve as a vent when needed.

It is also an object of nur invention to intro- 'Fixed to the top of the container by means of duce foam stabilizing solution into a water stream bolts 30, is a Venturi tube 29 which with gasket at a rate which varies automatically with any 3| closes the opening 28 in the container top I2. 45 variation in the rate of ilow of water. The entrance end 29a of the Venturi tube 29 may A further object of this invention is toprovide be connected, as by means of the coupling 32 and an apparatus for accomplishing the foregoing rea suitable hose (not shown), to a hydrant or sults automatically and without requiring the conother source of water under pressure. The presstant attention of an operator. sure of the water passing through the Venturi A further object of this invention is'to provide tube will vary at the diierent portions of the an apparatus for introducing a foam stabilizing tube, depending upon the design thereof andthe agent which accomplishes the foregoing objects cross sectional area of these portions. A `high and which may be easily transported to the depressure portion of the Venturi tube is prefersjrea placent use. ably connected throughthe passageway 33 and the auxiliary tube 34 to the top i2 of the container i0. Auxiliary tube 34 may be threaded into a solid portion of the tube 29 and is preferably provided with a suitable battling arrangement whereby water passing through the tube 34 is directed upwardly through the passages 35 in the head 36 against the side walls and upper portion of the opening 2B. The direct passage of water into the container through the' tube 34 may be prevented by the bolt 31 holding the baille plate 33 in place.

A low pressure portion of the Venturi tube 29 is preferably connected directly through the passageway 39 to a tube 40 which extends down into the container IU to a point adjacent the bottom thereof and which is open only at its lower end. Water carrying foam stabilizing material will thus iow out of the end 29h of the tube 29.

In the operation of this apparatus, water under pressure, as from a hydrant, is passed through the Venturi tube 29 in the direction of the arrows in Fig. 2. Container i0 has been previously filled with a solution 4I of a foam stabilizing agent and the cap 23 is tightly secured in place, the vent 2l being closed. yAs the stream of water flows through the Venturi tube, water under considerable pressure at the entering side of the Venturi tube passes by way of the passage 33, tube 34, and the bailieopenings 35 into the top of the container i0, thereby creating a considerable pres'- sure on the top of the solution in the container. The lowermost portion of the container is connected to a low pressure portion-of the Venturi tube 29 by the tube 4D and the flow of the foam stabilizing agent up through the tube 40 and into the stream of water in the Venturi tube 29 is thus produced. Such a. flow through tube 40 will depend upon the pressure differential between the high pressure portion of the venturi and the low pressure portion of the venturi selected, and the rate of ow of foam stabilizing, solution through the tube 40 will vary in accordance with the rate of flow of water through the Venturi tubev As water flows into the top of the containers,

the baiing arrangement prevents this water from being projected at high velocity into the foam stabilizing solution, and turbulence and Vmixing of the water with the foam stabinzig solution is thereby minimized. As foam stabilizing solution flows out of the bottom of the container, its place -is taken by the water owing in Y at the top, until'the foam stabilizing solution has been exhausted. Fig. 1 shows the apparatus during operation after a part of the foam stabilizing solution 4I has been withdrawn from the bottom of the container and has been replaced by the water 42 which has entered at the top thereof. The water is shut off after the solution has been used up, vent 21 is'opened, and the dumping valve I5 is opened by means of the handle I9 to remove the water from container l0. The valve i5 maythen be closed and the container can be quickly recharged with foam stabilizing solution through the opening 24. If desired, the water under high pressure may be taken from other portions of the water passage or ,the Venturi tube. For example the tube V34 may be connected to the Venturi tube 29 at the opposite end of the tube from that shown in Fig. 2.

In accordance with my invention, the foam stabilizing solution will be injected into the owing stream of water at the desired rate of flow and the stream of water carryingthe injected foam stabilizing material will be under prac. tically the same head as the stream of water approaching the Venturi tube 29. Any loss in head will be extremely small.

l While the stream of water carrying foam stabilizing material as it leaves Venturi tube 29 will be useful in connection with most methods of producing iire extinguishingfoam, it is particularly valuable when employed for the production of the so-called air foam, in which air is' aspirated by a stream of water in accordance with the principle described in the Wagener Patent No. 1,821,914. In, the art of producing air foam, it is very important to maintain the head of the water so that there willbe suflicient energy present in the resultant foam stream for projection upon the fire.

In the operation of the apparatus illustrated, the end 29h of Venturi tube 29 is preferably co'nnected to a suitable device for introducing air into the stream by the aspiration action thereof to produce fire extinguishing foam. Suitable apparatus for this purpose, which may be connected to 'the end 29h of the Venturi tube, is shown and described in my Patent Number 2,057,218 and in my copending applications Serial. No. 742,042, filed August 30, 1934 (now Patent 2,146,605, dated Feb. 7, 1939) and Serial No. 15,010, filed April 6, 1935. l

In the aspiration of air, a considerable amount the volume of air aspirated and, consequently, it is particularly important in this art to introduce the foam stabilizing solution into the stream of water with as little loss of head as possible.' The use of other sources of power, such as booster of energy of the stream is lost, depending upon 35 pumps, or power injectors for this purpose are necessary otherwise and detract from the mobility of the apparatus. Apparatus in accordance with this invention accomplishes the vobjects thereof in a simple manner, can be readily used where only ,4

hydrant water is available for producing and projecting foam, and provides a uniform quality of foam even though the pressure of the water available should vary from time to time.

In the specic embodiment of the apparatus illustrated, the solution of foam stabilizing material is shown as taken from the bottom of the container i0. This will be preferred where the foam stabilizing solution has a specic gravity greater than that of water. Where the foam .l

stabilizing solution is lighter than water, it will be apparent that the connections to the Venturi tube may be reversed to introduce water under higher pressure into the bottom of the container i0 and to withdraw the solution from the top l,

thereof.

In the practical operation of thisinvention it is also desirable to employ a container l0 of as small a cross sectional area as practical, in order to provide a relatively small area o f contact be- I claim:

1. Apparatus for introducing a solution of foam stabilizing material into a stream of Water 'comprising a passage for said stream constructed and arranged to provide oliierent pressures of water in different portions thereof by altering the velocity of said stream without more Athan normal losses in pressure due to friction, a closed container for a solution of foam stabilizing material,

means for introducing Water from a high pressure portion of said passage into said container, bame means for obstructing direct ow of Water into the container through said introducing means, and means for withdrawing solution from said` container at a point remote from the introduction of Water and introducing said solution into a 10W pressure portion of said passage.

tions thereof, a closed container for a solution of foam stabilizing material, means for introducing Water from a high pressure portion of said passage into the top of said container through a baie for reducing velocity and turbulence of the water entering "'said container, and means for withdrawingl solution from the bottom of said container and introducing ,said solution into a 10W pressure portion of said passage.

3. Apparatus for introducing a solution of foam stabilizing material into a stream of water comprising a passage for said stream including a Venturi section, a closed container for a solution of foam stabilizing material, conduit means conl necting a portion of said passage of larger cross- 

